Sewing-machine driving mechanism.



C. H. T; HAGELSTEIN.

SEWING MACHINE DRIVING MECHANISM.

APPLICATION FILED AUG.30, 1913- Patented Feb. 29, 1916.

2%? ceases,

CHRISTIAN H. T. HAGELSTEIN, OF BOSTON, MASSACHUSETTS, ASSIGNOR TO THE REECE BUTTON HOLE MACHINE COMPANY, OF BOSTON, MASSACHUSETTS, A CORPORATION OF MAINE.

' Specification of Letters Patent.

SEWING-MACHINE DRIVING MECHANISM.

Application filed August 30, 1913. Serial No. 787,434.

To all whom it may concern:

Be it known that I, CHRISTIAN H. T. HA- GELSTEIN, a citizen of the United States, residingat Dorchester, in the c1ty of Boston, in the county of Sufiolk and State of Massachusetts, have invented certain new and useful Improvements in Sewing-Machlne Driving Mechanism, of which the followmg 1s a specification, reference being had thereln to the accompanying drawing.

This invention relates to sewing machine driving mechanism and more partlcularly to a means for causing a stoppage of the stitching mechanism or of the machlne when, a sewing operation is concluded. While the mechanism hereof might be applicable tomany types of sewing machines it is for convenience shown applied to the type of sewing machine employed for fiIllShlIlg button-holes. In such a machine there is a driving shaft which rotates at fairly h1gh speed for operating the needles and other parts. At the end of an o eration 1t is sometimes desirable to stop t e stitching automatically, or the stopping means might be operated at will to bring the driving shaft to a stop at any time desired by the operator.

The present invention has for an object to provide an improved driving mechanism including stopping means for effectively stopping the driving shaft in a practically instantaneous manner, yet in such way as to avoid excessive shock, noise and wear upon the (mechanism and, at the same time, to accurately bring the parts to rest in any desired position, preferably with the needle or needles disengaged from the work.

To the attainment of such objects the present invention consists in the novel mechanisms, combinations, arrangements, details and other features shown and described in the accompanying drawings and specification.

First will be described one form in which the invention may be embodied, and thereafter the novel features will be pointed out in the claims. I

In the accompanyin "sheet of drawings forming a art hereof t single figure represents a right elevation of a portion of a buttonhole finishing machine emhodying'the present invention.

Features and details not fully disclosed herein will be understood to be of the Well known Reece type, such, for example, as illustrated in Patent No. 1,021,739.

The machine frame 10 has the usual overhanging arm 11. The driving shaft 12 extends horizontally and at its right end is loosely surrounded by a constantly rotating member or belt pulley 13 shown engaged by a belt 14; The shaft is shown as provided with a small hand wheel 15 at its right extremity between which and the pulley are located the hub and other parts later to bedescribed.

The driving pulley 13 is shown as grooved at 17. This groove is located at the right face of the pulley and the groove is formed between what may be termed the outer groove surface 18 and the inner groove-surface 19. This groove, which is partly eccentric or irregular, is for the reception of clutch dog later to be described.

Mounted fast upon the shaft 12 is hub 21, shown in dotted lines, forming a support for the dog, and this hub at its left or inner side has a depressed area 22, within which is located the pivot of dog 23. This dog at its extremity is provided with a leftward ing to hold the lug 24. in engagement with the irregular portion of the inner surface 19 of the groove 17. Extending substantially radially outwardly is the projection or tail portion 26 of the dog.

The mechanism thus far described is substantially old and well-known and needs no further elaboration than to explain that,

while the spring acts upon the dog and the lug of the latter is held against the inner surface of the pulley groove, the hub is caused to rotate with the pulley. Thereby the drivin shaft is actuated. When, however, the 0g is shifted in position by amovement against the spring the lug 24.- passes-into the open part of the groove so as to release the hub from the pulley. By now providing a relatively fixed stop or lug that can be struck'by the tail 26 of the dog a mutual engagement of the two will effect both a release of the hub and thereupon a stoppage of the hub and shaft. Heretofore different arrangements have been tried whereby the tail 26 can be encountered for stopping the driving shaft, but these ar- I chine.

movement of the arm 39 is afforded by the ing is generally tangential to the path of rangements have mostly proven either complicated and for that reason unsat1sfae-' tory, or inefficient and uncertain in action. The great shock caused by the impact of the tail against. the lug has not only an injurious effect, but also a tendenc to displace or throw back the relatively xed lug, thus permitting the dog to resume operative position and causing a resumption of rotation against the operators will.

The present stopping means has been found to be not only extremely simple and efficient, but also certain in its operation, non-destructive and comparatively quiet. Such'stopping device indicated generally at 30 is in the form of a lever having the swinging arm 31 which carries the lug, and the extension 32 which may be depressed by treadle or otherwise for holding the arm 31 lifted to permit the machines operation. Against the treadle action may be opposed a spring 33 tending to lower the arm 31 and bring the lug 34 into the path of the fast rotating tail 23.

The principle of the present improvement is substantially to permit a very limited yielding movement of the lug 34 when struck by the tail and'to oppose such movement by an extremely powerful yieldingresistance. This principle may be effected as shown herein by constructing the lug piece .34 in the form of a two-arm lever pivoted at 37 upon the heavy carrier or arm 31. Normally the lug body 34 rests against the heavy stop portion 38 on the arm 31, which affords one limit of movement. The other arm or extension 39 of thelug piece is shown as substantially parallel with the carrying arm31. The arm '39 is pressed outwardly 'or upwardly by a very powerful spring 40, which may yield slightly under the impact caused when stopping the ma- A positive stop for the yielding portion41 of the carrying arm and a convenient arrangement is to'provide such portion 41 in the form of a cylindrical socket forthe coil spring 40.

The operation of the mechanism thus described may be substantially as follow s: In

the position in which the parts are shown pact of the tail against the lug are partially eliminated and materially decreased by the slight yielding afforded by the, powerful spring 40. This slight movement is found to be suliicient for. that purpose and, at the same time, it prevents the lug 34 swinging to such extent as to endanger its secure holding of the tail26. The compression of the spring 40 is extremely high and may be such as'not to necessitate actual contact between arm 39 and socket 41. WVith the described to the hub 21 which latter is provided with a notch shown at 45, the latterto be engaged by the arm 44 when the parts are brought to rest, thus holding them against a resumption of operative position. When the arm 32 is depressed for starting the machine a pin 46 lifts the arm 44 out of the notch 45.

A spring 47 normally tends to hold the arm,

44 in engagement with the .pin 46. W hen 26 strikes 34 this brings 26 to rest and the momentum carrying the other rotating parts forward brings the notch 45 to the end of the lever 44. The lever 44, therefore, not merely prevents rebound, but, in efiect, compels 26 to remain in its relatively deflected position, thus rendering a resumption of driving conditions impossible.

The following further remarks will give a clearer understanding of the. nature of the improvement. The carrier, 3l.being swingingly mounted on the machine, is enabled at its free end to be moved toward andfrom the support, shaft or hub 21 for shifting the lug 34 between operative and inoperative positions. The means for movably fitting the lug to the carrier comprise a pivot, the lug pointing from the pivot toward the hub or shaft so that its movement or yieldrotation of projection 26. The spring 40 so presses upon the lug as to resist displacement by the impact of the projection, and

by the provision of the heavy stop 38 on the carrier the spring is enabled to be maintained always under high compression. According heretothe actual movement is sufficiently small to preclude any appreciable change of angle of the projection as the lug yields. Therefore the lug and projection, meeting with a normal blow, will not. change relation to such extent that the projection will tend to raise the lug andcarrier and es cape from them. Therefore the two can be made as shown with at least one of the meet ing faces substantially flat and radial, so that disengagement is afterward easily effected, where curved or hooked engaging parts would interfere with the action of lifttion of the machine. The arrangement of having the second arm 39 of the lever, whose first arm is the lug 34, at an angle to the lug gives efficiency of operation and compactness, since the second arm lies generally parallel with the carrierarm 31. This permits the spring 40 to be located at the end of the second arm. If the spring should yield excessively, the arm 39 is positively stopped, so that no excessive movement of the lug is possible. The spring 40, however, when of proper strength is found sufiicient, and, indeed, the use of a coil spring affords an increasing resistance which may amount to a positive stop if the coils should close into mutual contact.

It will thus be seen that a sewing machine driving mechanism has been described embodying the objects and advantages before referred to, and other advantages will be apparent to those skilled in the art.

Since many features of the construction, combination, arrangement and detail may be varied Without departing from the principles of the invention, it is not intended to limit the same to such features excepting so far as set forth in the appended claims.

What is claimed is: j

1. A driving and stopping mechanism, including in combination with the shaft to be rotated and stopped, a stop dog movably supported on, to rotate with, said shaft, and having connections for unclutching the shaft, and a stop device adapted to cooperate with said rotating stop dog tounclutch and stop the shaft at a suitable point; said device comprising a swinging carrier having a fixed pivot, a non-sliding stop lug swinging about a relatively fixed pivot on said carrier and adapted to shift with the carrier toward and from said shaft, said lug projecting from its pivot toward said shaft, a powerful spring tending to cushion said lug against the impact of said step dog with a minute yield, and an abutment normally opposing said spring, said parts so constructed and arranged that a line from said shaft to said lugs pivot stands substantially at right angles to a line from said carrier pivot to said lug.

2. A driving and stopping mechanism including in combination, a driver, as pulley 13, a rotatable shaft-part as hub 21, adapted to be clutched to or released from said driver for the purposes of driving and stopping, a stop dog movably supported on said shaft-part and having connection for unclutching the latter and having a stop projection. and a stop device adapted to cooperate with said stop dog to unclutch and stop the shaft-part at a suitable point; said device comprising a shiftable carrier, :1 stop lug pivoted on said carrier adapted to shift with the carrier toward and from said shaft-part, said lug projecting from its pivot toward said shaft-part, a lug extension beyond its pivot at an angle to the lug, a powerful spring acting on said extension tending to cushion said lug against the impact of said stop dog projection with a minute yield, and an abutment normally opposing said spring.

3. A driving and stopping mechanism in- .cluding in combination, a driver as pulley 13, a rotatable'shaft-part as hub 21, adapted to be clutched to or released from said driver for the purposes of driving and stopping, a stop dog movably supported on said shaft-part and having connection for unclutching the latter and having a stop projection, and a stop device adapted to cooperate with said stop dog to uncluteh and stop the shaft-part at a suitable point; said device comprising a swinging carrier adjacent the shaft-pa'rt periphery, a stop-lug pivoted at the free end of said carrier, the lug body projecting from its pivot toward said shaft-part and substantially at right angles to the length of the carrier, said lug having also an extension beyond its pivot and substantially parallel to the carriers length, a barrel-and-spring device on the carrier opposite the free end of the lug extension adapted to afford a powerful cushion and abutment for the lug movements when struck by said projection, and an abutment on said carrier cooperating with the lug body to normally oppose said spring.

4. A sewing machine driving mechanism including in combination, a constantly rotating member, a rotatable support adapted to be clutched to or released from said member,-a projection rotatable with the support and adapted to effect unclutching of the support, and a stopping device having a lug adapted to be shifted into the path of said projection for shifting the projection to release position and bringing the support to rest, and from the path thereof to permit the start of said support into rotation said stopping device comprising a shiftable carrier, a pivoted lever on said carrier, one arm of which constitutes said lug, the second arm of said lever standing at an angle to lug, stops arranged to permit a limited movement of the lever when struck by said projection, and a spring under powerful initial compression, acting on said second lever arm, arranged to hold the lever against one of its stops and to yieldingly resist displacement thereof when the lug and'projection meet.

5. A sewing machine driving mechanism including in combination, a constantly r0- tating member. a rotatable support adapted to be clutched to or released from said member. a projection rotatable with the support and adapted to effect unclutehing the support, and a stopping device having a lug adapted to be shifted into the path of said projection for shifting the projection to release position and bringing the support to rest, and from the path thereof to permit the start of said support into rotation; said 5 stopping device comprising a shiftable carrier, a pivoted lever on said'carrier, one arm of which constitutes said lug, the second arm of said lever standing at an angle to lug and substantially parallel to the carrier, 10 stops on the carrier arranged to permit a limited movement of the lever when struck by said projection, and a spring under powerful initial compression, between said carrier and said second lever arm, arranged to hold the lever against one of its stops and 15 to yieldingly resist displacement thereof when the lug and projection meet.

In testimony whereof I aflix my signature in presence of two Witnesses.

CHRISTIAN 11. T. HAGEL'STEIN.

Witnesses:

J. WARREN NICHOLS, WM. C. Borsvnn'r. 

